Recently leaked documents are raising new concerns surrounding Chinese tech giant Huawei. On Monday, leaked internal documents obtained by the Washington Post revealed Huawei worked with a Chinese-state owned tech firm for at least eight years on a variety of projects centered in North Korea. One of those projects included the development and maintaining of the country’s first commercial 3G wireless network.

The detailed spread sheet was shared by a former Huawei employee, who claimed the information is of public interest. However, the person’s identity has not been released out of fear of retaliation.

If the reports are true it would bring up a new conflict between the U.S. and China as such a move would raise questions of whether Huawei, which has used U.S. technology in its components, violated American export controls to send equipment to North Korea.

The documents appear to confirm what U.S. officials have long feared — that Huawei is a national security risk.

“…you’ve seen…our effort to ensure that the networks in which American information flows are trusted, that we understand where that information is going, who’s the end user, and wanting to make sure the information doesn’t end up in the hands of the Chinese Communist Party.”

— Mike Pompeo, U.S. Secretary of State

This latest development comes after the Trump administration agreed in June to lift some sanctions on the company, allowing U.S. companies to sell certain products to the the Chinese tech giant.

According to the Washington Post, Huawei has not directly responded to the report, but a spokesperson said the company does not have business in North Korea.